Fix SKP version in tasks.json, make upload_skps.py update tasks.json

infra/bots/tasks.json

 {
   "jobs": {
     "Build-Ubuntu-GCC-x86_64-Release-GN": {
       "priority": 0.8,
       "tasks": [
         "Build-Ubuntu-GCC-x86_64-Release-GN"
       ]
     },
     "Housekeeper-PerCommit-InfraTests": {
       "priority": 0.8,
@@ skipping 120 matching lines @@
     "Perf-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-GN": {
       "cipd_packages": [
         {
           "name": "skia/bots/skimage",
           "path": "skimage",
           "version": "version:8"
         },
         {
           "name": "skia/bots/skp",
           "path": "skp",
-          "version": "version:10"
+          "version": "version:12"
         },
         {
           "name": "skia/bots/svg",
           "path": "svg",
           "version": "version:3"
         }
       ],
       "dependencies": [
         "Build-Ubuntu-GCC-x86_64-Release-GN"
       ],
@@ skipping 26 matching lines @@
     "Test-Android-Clang-AndroidOne-GPU-Mali400MP2-arm-Release-GN_Android": {
       "cipd_packages": [
         {
           "name": "skia/bots/skimage",
           "path": "skimage",
           "version": "version:8"
         },
         {
           "name": "skia/bots/skp",
           "path": "skp",
-          "version": "version:10"
+          "version": "version:12"
         },
         {
           "name": "skia/bots/svg",
           "path": "svg",
           "version": "version:3"
         }
       ],
       "dependencies": [
         "Build-Ubuntu-Clang-arm-Release-GN_Android"
       ],
@@ skipping 25 matching lines @@
     "Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-GN": {
       "cipd_packages": [
         {
           "name": "skia/bots/skimage",
           "path": "skimage",
           "version": "version:8"
         },
         {
           "name": "skia/bots/skp",
           "path": "skp",
-          "version": "version:10"
+          "version": "version:12"
         },
         {
           "name": "skia/bots/svg",
           "path": "svg",
           "version": "version:3"
         }
       ],
       "dependencies": [
         "Build-Ubuntu-GCC-x86_64-Release-GN"
       ],
@@ skipping 108 matching lines @@
         "patch_storage=<(PATCH_STORAGE)",
         "rietveld=<(CODEREVIEW_SERVER)",
         "issue=<(ISSUE)",
         "patchset=<(PATCHSET)"
       ],
       "isolate": "upload_dm_results.isolate",
       "priority": 0.8
     }
   }
 }